Hi,
No you'll need to use the payment plugin corresponding to the payment gateway you'll want to use.
You would only have to build your own payment plugin if there isn't any for the payment gateway you choose.
Either way, you won't need to use the HikaShop credit card plugin.
Different payment gateways will work differently. For example, with PayPal standard, the payment plugin won't display the credit card form on your checkout, but after the checkout, on a PayPal payment page hosted by PayPal. However, the PayPal Pro plugin will display the credit card form on your checkout and the payment will happen when you finish the checkout.